A rifle or other hand-held weapon which is aimed at a target is provided with a sight that aids the user in aligning the weapon with the target. The weapon may be provided with a telescopic sight which includes a variable lens group that may be controlled by the user to change the magnification and field of view of the sight, between a lower magnification with a wider field of view, and a higher magnification with a narrower field of view. In either case, light enters the sight through an entrance pupil and passes through an exit pupil that defines the size of the image viewed by the user. The exit pupil may be defined by the diameters of the lenses, or, more commonly, by an aperture stop.
To use the sight properly, the user's eye must be aligned with the exit pupil in order to see the image produced by the sight, and must be at the eye relief distance behind the exit pupil. If the user's eye is not aligned with the exit pupil, none or only a portion of the image is visible to the eye.
The telescopic sight is typically used at the lower magnifications for short-range, close-quarters situations, and at the higher magnifications for long-range situations. The telescopic sight in its lower-magnification configuration may also be initially used in long-range situations to locate the target, and then the sight switched to the higher magnification for precise aiming.
Experience has shown that it can be difficult for the user to acquire (locate) the target at different magnifications of the telescopic sight, and to keep the target under surveillance as the telescopic sight is switched between different magnifications. There is a need for an improved approach to such a telescopic sight that overcomes such problems. The present invention fulfills this need, and further provides related advantages.